Machine for operating a piercercarrying plunger both to pierce and advance the work being operated on



Feb. 10, 1953v D. D. DUNCAN 2,

MACHINE FOR OPERATING A MERCER-CARRYING .REUNGER BOTH TO PIERCE AND ADVANCE THE WORK BEING OPERATED ON Filed April 22, 1950 I u m n ,m. 0,. mu..." "I.

1 5 q a; 40 15 ,Z7AN1ILD.B0NCAAI,

65 jz INVENTOR.

64- W 1 a 21 k Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE ERATED ON Daniel D. Duncan, Glendale, Calif.

Application April 22, 1950, Serial No. 157,452

6 Claims.

, 1 My invention relates to a machine for operating a piercer-carrying plunger both to pierce and advance the work being operated on.

Heretofore leather puncturing machines have utilized the piercing member only to puncture the work, and such machines have therefore been provided with auxiliary means independent of said piercing member to advance the work in the required step-by-step fashion between puncturing operations. By the present invention there is provided an assembly of guide members for the piercer-carrying plunger which guides the plunger in such a manner that, at the completion of each puncturing operation said member advance the work to the position required for the next puncturing operation, said assembly of guide members automatically restoring the plunger to its original position after each puncturing operation.

A more specific object is to provide, to cooperate with the aforesaid assembly of plunger guiding members, a strap metal plunger having a sidev edge portion so contoured as to form a cam face engageable by a stationary adjustable part which, when encountered by said cam face causes said plunger, during the final part of its downward movement to swing in a direction to cause the piercer carried by its lower end to advance the sheet material being operated upon to the proper position for having the next puncture made throughit.

Also it is an object of the present invention to. provide .an improved presser foot stripper to vention will hereinafter appear.

Referring to the accompanying drawing, which .illustrates a preferred embodiment of the invention, now reduced to practice,

Fig. 1 is a front perspective view of thedevice, showing the same mounted upon a work. table, fragmentarily shown, a part of the operating lever being broken away to. contract the view.

Fig. 2is a vertical .sectionon line 22 of Fig. 3.

Fig. 3 is an. elevation looking at the front side of the device, .the front casing cover being removed, the. needle or piercer being in the elevated position shown in Fig. 2.

Fig. 4. is a reproduction. of Fig. 3 except that part are shown in section and the piercer and operating lever areshown at the lower, instead of upper, limit of their travel.

Fig. 5' is a transverse section on. line 55 ,of

Rig. 3.

Fig. 6 is a perspective view separately showing theneedle or piercer guide disk.

Referring in detail to the drawing, the invention therein illustrated is embodied in a leather punching or piercing machine comprising a base plate In to which is secured an upstanding casing ll, said casing housing an upwardly and downwardly extending plunger [2 which carries at its lower end a needle or piercer l3 and which has its upper end portion operatively connected with a manually operable lever l4 by means of'a pair of toggle links I 5.

The, aforementioned base plate I!) is shown countersunk flush with the upper surface of a'sub base 26 which may be the top of a bench or'work table, screws 2] or other fasteners securing said base plate to said sub-base. As well shown in Fig. 2, the thick base plate ID has through it a circular bore .22 the upper part of which is diametrically enlarged to form an annular shoulder 23 upon which i seated the peripheral, flanged portion of a needle or piercer guide disk 24 which fits within the enlarged upper part of said bore 22. Said disk is provided with guide slots 25 and 26 for the piercing member l3, said slots extending diametrically of the disk and intersecting each other at a right angle. The slots 25 and 26 are substantially equal in length, but the former slot is somewhat wider than the latter. The disk, 24' frictionally maintains itself in rotationally adjusted position when set for either the use of the wider slot 25 or of the narrower slot 26. Said two slots accommodate difierent sizes of piercers used upon the work.

An elongated pressure foot 30 extends diametrically across and normally seats yieldably upon the upper face of the aforesaid guide disk 24. To each end portion of said pressure foot is secured a rearwardly extending strap metal arm. 3 I, the rear part of each of these arms being pivoted at 32 to the adjacent side, of a basal extension Ha that projects rearwardly from the casing ll. Each of said arms 31 is shown downcasing II has in it: a broad rectangular bottom recess 36 which extends all the way across the front-to-rear dimension of said foot part Ila and, at each side of said recess screws 31 extend through the intact portion of said part and secure it to the aforesaid base plate It. In said recess 36, having a working fit across its width, is a work gage plate 38. Said plate as viewed in Fig. has a rectangular front end portion and has its rear end portion beveled at one side and rounded at its extremity as indicated at 39. After loosening its set screw 38a said gage plate may be adjusted forwardly or rearwardly from the position thereof shown in Fig. 5; or it may be removed and turned end-for-end so that its rounded end portion 35 is presented to the work. In the latter position it will guide the operator in making a row of punctures or slits parallel to an in-curved edge portion of the work.

Underlying the aforesaid base plate It is desirably placed a sheet like of slightly compressible material so that the point of the piercer !3 will not be damaged by engaging material injurious thereto.

The casing structure ll includes a sturdy, up-

standing back wall 46 which is braced along its midwidth by an upwardly tapering rib M, desirably integral with said wall and the already mentioned basal part Hu. of said casing. Said wall and basal part Ha are additionally united by a forwardly and upwardly directed angular extension 42 of said basal part Ha. By this arrangement an alcove 43 (see Fig. 2) is provided, open in front and at each side, which affords a spacious clear space in which to adjust the work (shown as a strip of leather 44), forwardly and rearwardly in relation to the piercer 13.

Above said alcove 43 the casing wall 45 is provided with a horizontal, forwardly directed top flange 41 and at one side with a vertical forwardly directed flange 48, a like vertical flange 49 extending along the opposite side thereof, said flanges being respectively inwardly thickened at 48c and 48a superjacent to said alcove 43. A

.cover plate 50, in an overlying, attached relation to said flanges 47, 48 and 49 completes a housing for the greater portion of the punch operating means, presently to be described.

The casing flange 49 is provided with a vertical slot 49s in which swings the aforesaid lever H. At one end said lever carries a handle portion 52 and its opposite end is swingably attached by a pivot screw 53 to the adjacent upper corner portion of the casing. A wire spring 54 has its mid-length portion coiled around said screw. Said spring 54 has one limb 54a abutted against the casing side flange 4B and has its other limb 5% provided with a hook that underlies the lower edge of the lever M at a point spaced away from the fulcrum screw 53. Said spring tends to swing said lever upwardly from the downswung position thereof shown in Fig. 4 to its upswung position shown in Fig. 2.

The aforesaid pair of twin toggle links H3 includes within its upper end portion the lever It at a point considerably spaced from the lever fulcrum screw 53, the upper end portion of the plunger l2 being narrowed where it is included within and pivoted to the lower end portion of said pair of links. Farther down said plunger has cut into its right hand side (as viewed in Figs. 3 and 4) a rectangular notch 55, and from the lower end of this notch downwardly said plunger is recessed in a manner to provide an inclined cam edge 56, a straight dwell 51 and at the lower end of said dwell an upwardly facing shoulder 58.

The upper end of notch 55 forms a downwardly facing shoulder 55a with which cooperates a pivotally mounted dog 59, the downwardly directed free end portion of which is continuously pressed against the plunger 12 by means of a spring 69.

With the aforesaid cam edge portion 56 and dwell 5'! of the plunger :2 cooperates an adjustable guide screw 6| which extends through a screwthreaded bore provided for it through the aforementioned thickened portion 49a of the casing wall. Said guide screw 51 also cooperates with aforesaid shoulder 58 (see Fig. 3) to stop the upward movement of the plunger i2.

With the opposite side of the plunger I2 cooperates additional guide means comprising a pendant guide arm 63 the upper end of which is pivotally fastened to the casing by a screw 53a and the socketed lower end of which seats oneend of a compression spring t l which continually swingabiy presses the lower part of said arm against the plunger 12. Farther down the same side said plunger is at times engaged by the inner end of a guide screw 65, to which a screwdriver may be applied to adjust it as desired. Said screw 55 is shown extending through a screwthreaded bore provided for it through the thickened casing wall portion tau, and is furnished with a look not 55a safely to keep it in adjusted position.

The aforementioned piercer i3 is shown removably held in place by a set screw l3a. As shown in the drawing this member has a flattened point portion adapting it for producing a row of short slits through the leather strip or sheet 44, but obviously various other slitting, holecutting or puncturing members may be substituted, if desired.

Starting the operation with the lever 14 and plunger [2 at the upper limit of their travel as shown in Fig. 3, it will be seen that, during the first part of the downward movement of the plunger the link structure 15 is positioned at one side of dead center in relation to the plunger, and from Fig. 4 it is seen that said link structure has swung to the opposite side of dead center during the downward movement of the operating lever and plunger.

During the operation of the device the lever, link structure and plunger are kept in proper operative positions between the casing back plate M and the face plate 50.

During the initial part of each downward movement of the lever I l the piercer moves vertically down through the work, the inner end of the screw 6| at this time moving adjacent to the dwell 51 without causing any swinging movement of the plunger. But as soon as the piercer has advanced sufficiently through the work complete ly to pierce it, screw BI starts to act upon the cam 58 to cause the plunger to swing from the position shown in Fig. 3 to that shown in Fig. 4. This swinging movement of the plunger causes the piercer to advance the work to the limit set by the adjustment of screw 65, thus completing the spacing for the next piercing of the work.

Releasing downward pressure upon the handle 52 of the lever I4 permits spring 54 automatically to elevate the lever together with the mechanism operatively connected thereto, to the normal position. During the automatic elevating of said lever l4 spring-pressed guide arm 63, in =co-operation with the spring pressed dog 59, brings the plunger to the position shown in Fig. 3 preparatory to vertical downward movement during the next depression of said lever. During the upward movement of said plunger, the rounded outer end-of the dog" 59-p-re'sses continuously against 'theadja'cent side-of the plunger, so that said plunger maintained swung over toward its 'startingjposition until the needle is elevated-out of the work. The pressure of the dog upon the plunger is. particularly important as the latter approaches its uppermost position, shown in Fig. 3, for the link; Ehas thenceased to pull the upper part of the plunger toward the pendant arm 63, leavingit entirely-'tothedog'to perform that function. The point of the needle will clear the work slightly "before the dog drops" into the notch 55 in. the plunge-r, and when the dog drops into .said notch it allows the spring pressedpendant alrmfiii to swing the plunger back;to the starting position.-

litwilllbe -s'een that the dog 59, screws. Eliand. 165i and.-spring-pressed' pendant arm E3qcooperate to term the already mentioned assembly of plunger-guiding members which guide the plunger vertically downward during the piercing operationand thereupon duringt-he remainder. of

its downward movement, swing its lower end-in a direction to advance the work in accordance with the spacing in a row of punctures 'being formed by the operation of the machine.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the subject matter claimed.

Iclaim:

1. In a machine of the kind described, a base plate, a casing mounted upon said base plate, an

upwardly and downwardly extending plunger supported by said casing for vertical movement and carrying a piercer for operation upon sheet material resting fiatwise upon said base plate, said plunger normally extending substantially vertically, a manually operable lever mounted upon said casing and linked up with said plunger so as to move the latter downwardly, a spring carried by said casing and operatively connected with said lever to lift the latter and said plunger to the upper limit of their travel after depression of said lever, guide means carried by said casing directing said plunger and the piercer carried thereby vertically downward until the latter has performed a puncturing operation through said sheet material and subsequent to the puncturing adjacent punctures in the row of punctures being formed by the operation of the machine, and

means carried by said casing and cooperating with said plunger after the piercer has moved laterally to feed the work to elevate the pier-oer out of the work prior to swinging over to starting position.

2. In a machine of the kind described, a base plate, a casing mounted upon said base plate, an upwardly and downwardly extending plunger supported by said casing for vertical movement and carrying at its lower end a piercer for operating upon sheet material resting fiatwise upon said base plate, said plunger normally extending substantially vertically, a manually operable lever carrying at one end a handle portion and at its opposite end being swingably attached to said casing, a link structure one end of which is attached to said lever at a point spaced away "from its said attached end, said link structure extending downwardly from said lever and having its lower end pivotally connected to the upper plunger and the piercer carriedthereby vertically downward until thel'atter-has' performed-a puncturing operationthroughsaidsheet'material and subsequent to the puncturing operation impart a swinging movement to said plunger tocause said pierce-r to advance the sheet material in accordance with the spacing between adjacent punctures in the row orpunctures'being formed .by the operation or the machine, :said guide means comprising mechanism to actfuponx'the plunger to efiectsaid swinging m'ovementjgand means carried by .said casing and :oo'operatin'g with said plunger after the 'piercer has'imoved laterally to advance the work to. elevate :the piercer out of the work ,prior'to swingingjover to starting. position, said link structure swinging from one to the opposite 'side of dead center during the downward travel of said plunger.

3. In a machine of the kind described, a base plate, a casing mounted upon and upstanding from said base plate, a lever fulcrumed to the upper part of said casing to swing in a vertical plane, linkage pivotally connected with said lever and extending downwardly therefrom, a strap metal plunger carrying a piercer at its lower end and having an upper end portion pivotally connected with said linkage for upward and downward movement by said lever, said plunger being straight along one side edge and having its opposite edge contoured to form a cam portion, an adjustable screw carried by said casing and positioned to cooperate with said cam portion to cause said plunger when moved downwardly by said lever to swing away from said screw, an adjustable stop screw carried by said casing in a position to engage the side edge of the plunger which is opposite to the first recited screw, spring pressed means above said stop screw engaging the same edge of the plunger as the latter, said screw which acts upon said cam portion causing the plunger to swing during the final part of its downward movement in the direction and to the extent required to advance the punctured work in accordance with the spacing in a row of pun-ctures being formed by the operation of the machine, and means carried by said casing and cooperating with said plunger after the piercer has moved laterally to feed the work to elevate the piercer out of the work prior to swinging over to starting position.

4. The subject matter of claim 3, and said cam portion extending upwardly and outwardly from a notch in the plunger, said notch having a straight bottom which forms a dwell along which the first recited adjustable screw travels during the initial portion of each downward travel of said plunger.

5. In a machine of the kind described, a base plate, a casing mounted upon and upstanding from said base plate, a lever fulcrumed to the upper part of said casing to swing in a vertical plane, linkage pivotally connected with said lever and extending downwardly therefrom, a strap metal plunger having an upper end portion pivotally connected with said linkage for upward and downward movement by said lever, said plunger being straight along one side edge and having its opposite edge contoured to form a cam portion and a downwardly facing shoulder superjacent to said cam portion, adjustable means carried by said casing in a position to be engaged by said cam portion during downward movement of said plunger, a spring pressed dog carried by the casing in a position to engage and move upwardly across said shoulder during the time that said cam portion is being engaged by said adjustable means, adjustable stop means carried by the casing in a position to engage that side of said plunger which is opposite to said dog and adjustable cam-engaging means, and spring pressed 7 means above said stop means engaging the same side of the plunger as the latter, said adjustable means which is engaged by said cam portion causing the plunger to swing during the final part of its downward movement in the direction and 8 straight side portion against all parts of which the plunger abuts during the initial portion of the downward movement of the latter, the plunger abutting only against the lower part of said straight side during the final portion of its downward movement.

DANIEL D. DUNCAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 10,710 North Apr. 6, 1886 172,540 Woodrufi Jan. 18, 1876 1,156,824 Schwimmer Oct. 12, 1915 1,326,238 Walker Dec. 30, 1919 1,964,910 Glasson July 3, 1934 2,078,336 Merrick Apr. 2'7, 1937 2,097,568 Keall Nov. 2, 1937 2,123,875 Batchelder July 19, 1938 2,215,643 Gorham Sept. 24, 1940 2,582,813 Berridge et al Jan. 15, 1952 

